A tour bus slammed into a tunnel wall in the Swiss Alps in a horrific accident that killed 22 school children and six adults returning to Belgium from a joyous ski vacation, police said Wednesday.

Another 24 students were hospitalized, police spokesman Jean-Marie Bornet told The Associated Press, after the worst highway tunnel accident in Swiss history left the front of the bus mangled, trapping some people inside. The police chief described a "scene like a war."

The bus driver, about the only person who could explain exactly what happened, died in the crash, CBS News correspondent Charlie D'Agata reports.